A study published in 2015 in Advances in Nutrition suggests that taking omega 3 fatty acid supplements particularly docosahexaenoic acid (DHA) can help reduce risk of hepatic injury induced by Western diet and liver cancer.

Western diet can cause nonalcoholic fatty acid disease such as hepatosteatosis.  Hepatic injury, inflammation and oxidative stress can further worsen the hepatic condition and causes cirrhosis - a risk factor for hepatocellular carcinoma or liver cancer. 

The study conducted in mice that are prone to developing a type of nonalcoholic steatohepatitis when fed the Western diet shows that omega 3 fatty acids like DHA and eicosapentaenoic acid (EPA) can help alter hepatic metabolism and reverse the diet-induced oxidative stress and fibrosis.

The study suggests that DHA may be used to prevent nonalcoholic steatohepatitis and reduce risk of liver cancer.

DHA is one of commonly seen omega 3 fatty acids found in marine algae and cold water fish such as salmon.  Short chain fatty acids found in foods such as flaxseed can also be used in the body to produce a small amount of DHA.  For a therapeutic effect agaist diseases such as cancer, high doses of DHA are needed.  DHA in softgel prepared from marine algae can be purchased from online health stores.  (David Liu)

Donald B Jump, Christopher M Depner, Sasmita Tripathy, and Kelli A Lytle, Potential for Dietary ω-3 Fatty Acids to Prevent Nonalcoholic Fatty Liver Disease and Reduce the Risk of Primary Liver Cancer, Adv Nutr November 2015 Adv Nutr vol. 6: 694-702, 2015